If you are looking forward to building consumer based apps then niche areas such as healthcare, populist areas such as messaging, beautifully designed games(recommended platform: Unity) are better. Fermium apps with in app advertising is better is because of lower per capita income population audience. You may also create an ios version if the android version is successful. Another area which has a huge scope is big data/analytics apps, connecting consumers to business, advertisers.
Aabasoft being an IT company provides training that makes you industry ready.Students are trained to become independent android developers through java. A knowledge on java is desirable, if not it is provided.